The photoelectricity pulse detecting device
Technical field
This utility model relates to a kind of pulse detection equipment, especially relates to a kind of photoelectricity pulse detecting device that adopts the infrared light technology.
Background technology
Pulse is physiological phenomenon common in clinical examination and physiological Study, has comprised the important physiologic information of reflection heart and blood vessel state.The information such as the health status of each organ, pathological changes will be apparent in pulse in some way namely in pulse condition in human body.Be rich in the multidate information of the systems such as relevant heart, inner-outer circulation and nerve in the human body pulse condition.Contain many information that diagnostic value is arranged by pulse wave is detected the sphygmogram that obtains, can be used for predicting the conversion trend of the dirty 26S Proteasome Structure and Function of some device of human body.As: the variation of blood vessel geometric shape and mechanical property can cause the change of the character such as pulse waveform and velocity of wave, and the Pathophysiology of pulse sexually revises the various cardiovascular events of normal initiation, the change of pulse physiological property can occur prior to the disease clinical symptoms, can assess the vascular lesion that causes as hypertension and diabetes etc. by the detection to pulse.Simultaneously, pulses measure also provides a kind of physiology reference signal for blood pressure measurement, blood flow measurement and some other physiological detection technology.
Traditional pulse test method is confined to manual testing or stethoscope test, is subjected to artificial influence factor larger, and certainty of measurement is not high.Utilizing blood is highly opaque liquid, and the penetrance of illumination in general tissue can detect pulse signal by sensor than the characteristics of large tens times in blood.The characteristics such as that this technology has is simple in structure, good reproducibility are also the developing direction of biomedical engineering field simultaneously.
Summary of the invention
The purpose of this utility model is to provide a kind of photoelectricity pulse detecting device.
This utility model is provided with photoelectric sensor circuit, signal controlling and treatment circuit, warning circuit, display circuit and RS232 serial ports; Described photoelectric sensor circuit is provided with infrared light emission circuit and infrared light receiving circuit; Described finger is placed between infrared light emission circuit and infrared light receiving circuit; Described signal controlling and treatment circuit are provided with prime processing and amplifying circuit, filter circuit, rear class amplifying circuit, sample circuit, waveform changing circuit and single-chip microcomputer treatment circuit; The outfan of the input termination infrared light receiving circuit of described prime processing and amplifying circuit, the input of the output termination filter circuit of prime processing and amplifying circuit, the input of the output termination rear class amplifying circuit of filter circuit, the outfan of rear class amplifying circuit connects respectively the input of sample circuit and the input of waveform changing circuit, and the outfan of sample circuit and the outfan of waveform changing circuit connect respectively the single-chip microcomputer treatment circuit; Warning circuit, display circuit and RS232 serial ports are connected with the output port of single-chip microcomputer treatment circuit and are connected.
Described infrared light emission circuit and infrared light receiving circuit can adopt infrared tube.Described warning circuit can adopt buzzer etc., and described display circuit can adopt liquid crystal display, for example the DMD48270T047 display of Beijing Dwin Technology Co., Ltd..
This utility model adopts the RS232 serial communication.During at infrared tube middle, along with beating of heart, the blood capillary of finger tip produces corresponding volume-variation when banjo splint, and the light that the infrared light emission circuit sends specific wavelength is received by the infrared light receiving circuit after through finger.This process is detected after physiological amount (pulse of human body) converts optical signal to, and optical signal is converted to the signal of telecommunication by photoelectric device, and the signal of telecommunication shows by liquid crystal display after single-chip microcomputer is processed through amplifying and Filtering Processing is sent into single-chip microcomputer.
Collecting part of the present utility model adopts infrared tube, directly optical signal is converted to digital signal, and circuit is simple, and it is convenient to gather.Through test determination: this utility model can be realized easy and the precision measured, can measure the pulse of human body 1min within the time less than 30s, guarantees that error is in 2 times.Simultaneously can the display pulse waveform, reach the purpose of measuring easily and fast, exactly pulse.The utlity model has the characteristics such as functional, simple in structure, that cost performance is high, output display is stable, be particularly suitable for the clinography that family carries out self-examination and hospital nurse every day.
Description of drawings
Fig. 1 is the structure composition frame chart of this utility model embodiment.
Fig. 2 is that the prime of this utility model embodiment is processed and the amplifying circuit schematic diagram.
Fig. 3 is the filter circuit schematic diagram of this utility model embodiment.
Fig. 4 is the rear class amplifying circuit schematic diagram of this utility model embodiment.
Fig. 5 is the signal acquisition circuit schematic diagram of this utility model embodiment.
Fig. 6 is the Design of System Software flow chart of this utility model embodiment.
The specific embodiment
The utility model is described in further detail below in conjunction with drawings and Examples.
Referring to Fig. 1~5, this utility model embodiment is provided with photoelectric sensor circuit 2, signal controlling and treatment circuit 3, warning circuit 4, display circuit 5 and RS232 serial ports 6; Described photoelectric sensor circuit 2 is provided with infrared light emission circuit 21 and infrared light receiving circuit 22; Described finger is placed between infrared light emission circuit 21 and infrared light receiving circuit 22; Described signal controlling and treatment circuit 3 are provided with prime and process and amplifying circuit 31, filter circuit 32, rear class amplifying circuit 33, sample circuit 34, waveform changing circuit 35 and single-chip microcomputer treatment circuit 36; The outfan of the input termination infrared light receiving circuit 22 of described prime processing and amplifying circuit 31, the input of the output termination filter circuit 32 of prime processing and amplifying circuit 31, the input of the output termination rear class amplifying circuit 33 of filter circuit 32, the outfan of rear class amplifying circuit 33 connects respectively the input of sample circuit 34 and the input of waveform changing circuit 35, and the outfan of the outfan of sample circuit 34 and waveform changing circuit 35 connects respectively single-chip microcomputer treatment circuit 36; Warning circuit 4, display circuit 5 and RS232 serial ports are connected and are connected with the output port of single-chip microcomputer treatment circuit 36 respectively.
Described infrared light emission circuit 21 can adopt infrared tube with infrared light receiving circuit 22.Described warning circuit can adopt buzzer etc., and described display circuit can adopt liquid crystal display, for example the DMD48270T047 display of Beijing Dwin Technology Co., Ltd..
Banjo splint is in the centre of infrared tube, and due to beating of heart, the corresponding variation occurs the microvascular volume of finger tip, and (when heart shrank, the blood capillary volume increased; When the heart diastole, the blood capillary volume reducing), when the light that infrared transmitting tube sends is mapped to photoelectric device by finger tip, produce photoelectric effect, optical signal is converted to the signal of telecommunication, thereby obtains pulse information.
Be illustrated in figure 2 as prime and process and amplifying circuit, it forms every straight low pass inverting amplifier by one, removes DC voltage, suppresses high-frequency signal, the 50Hz power frequency is disturbed tentatively decayed, and simultaneously useful pulse signal is carried out preliminary amplification.It is 10 times that elementary amplification is set, and the cut-off frequency scope is 0.05~20Hz.Figure 3 shows that filter circuit, this filter circuit adopts three rank Butterworth low-pass filter circuits, and cut-off frequency f=10Hz is set, and the noises such as 50Hz power frequency are carried out larger decay, can remain with the pulse low frequency signal of use.Figure 4 shows that the rear class amplifying circuit, adopt the variable gain see-saw circuit, C6 and R12 consist of low-pass filtering, and cut-off frequency is 20Hz, and signal is amplified 10~100 times, and low-pass cut-off frequencies is 20HZ, filtering High-frequency Interference again.Figure 5 shows that Acquisition Circuit, the Schmidt trigger that adopts 555 intervalometers to be connected into, capacitance adopts 0.01 μ f, and sine wave directly is converted to square wave, sends in single-chip microcomputer, guarantees accurately, facilitates acquired signal.
Signal processing circuit adopts the Atmega16 single-chip microcomputer to realize the calculating pulse function that system is most crucial.The method of counting is to utilize the timer of single-chip microcomputer, calculates the time of a heart beating, then goes out frequency by this computation of Period, then can obtain the Pulse Rate of a minute.Consider the accuracy of calculating, measure 20 times heartbeat signal, extrapolate accordingly the pulse of 1min.The system that can realize will measure the pulse of human body 1min within the time less than 30s, and guarantees that error is in 2 times.Be illustrated in figure 6 as the Design of System Software flow chart of this utility model embodiment, adopt external interrupt, use the intervalometer timing, thereby calculate Pulse Rate.And waveform is sent in single-chip microcomputer in real time, changes and show by DA.
This utility model adopts the RS232 communication, and is convenient and swift, in real time reading out data.Ordinary person's Pulse Rate is that 60~80 times/min. baby is 90~100 times/min, and the old man is 100~150 times/min; So when occurring less than 60 times/min with greater than 150 times/min in system, the warning circuit automatic alarm, abnormal conditions appear in expression.Adopt the DMD48270T047 color display of Beijing Dwin Technology Co., Ltd. in display circuit, the display pulse number, and can show pulse wave in real time, visual in image, easy to operate.